A conventional type of household compactor has a ram that is positioned within a cabinet above a receptacle containing refuse to be compacted. During a cycle of operation, an electric motor drives the ram downward into the receptacle to compact refuse therein and then returns the ram to its rest position above the receptacle. The motor is controlled by a number of electrically interlocking switches and relays to move the ram during a refuse compaction cycle and protect the user from injury by the ram. For example, the motor is de-energized automatically if the receptacle is opened or tilted, or if the ram reaches its rest position at the completion of a compaction cycle. The direction of rotation of the motor reverses automatically to reverse the direction of movement of the ram following compaction of the refuse or upon a jam, detected by a centrifugal switch mechanically coupled to the motor, to return the ram to the rest position.
The refuse is generally contained in a disposable bag within the receptacle to be discarded when the bag becomes filled to its capacity. Because the interior of the receptacle of the compactor is not readily viewed, however, it is not convenient for the user to determine when the refuse bag should be removed and replaced. Even as the interior of the receptacle is viewed by the user as he or she slides the receptacle open prior to a compaction cycle, it cannot be determined by visual inspection whether the bag should be replaced prior to the next compaction cycle because the refuse added has not yet been compressed. It accordingly is desirable to provide a display to indicate whether the refuse bag of a compactor is full without requiring visual inspection of the bag by the user.
Apparatus in the prior art for providing a "full bag" indicator require the addition of multiple electrical components and therefore add excessively to the cost of the compactor. For example, in U.S. Pat. No. 3,831,513 to Tashman, a limit switch extending downward on a pipe from an upper surface of an industrial compactor contacts an abutment member on the ram when the ram is extended downward to a position corresponding to a full condition of the receptacle. The reactive pressure of refuse in the receptacle against the ram is detected by a centrifugal switch coupled to the motor that closes when the speed of the motor is reduced below about 1375 rpm as the ram compresses the refuse. If the limit switch is closed when the direction of the ram reverses in response to reactive pressure of the refuse in the receptacle, the receptacle is determined to be full. A relay having its actuator coil in series with the limit switch and centrifugal switch closes to energize a "full compactor" indicator lamp when both switches are closed simultaneously.
An additional pair of contacts of the indicator lamp relay, when the contacts are closed, electrically bypasses the limit switch and centrifugal switch to latch the indicator lamp on until the compactor is emptied and the relay reset.
This system, although effective to turn on the "full compactor" lamp when the receptacle of the compactor is full of refuse, requires in addition to standard compactor control circuitry as well as a downwardly extending limit switch and its suspension hardware, a further pair of relay contacts together with associated wiring for latching the indicator lamp on, and accordingly, is too costly for incorporation as a "full bag" indicator in a household compactor.
It is therefore an object of this invention to provide a "full bag" indicator for a compactor that is less expensive than indicators of the prior art.
Another object of the invention is to provide a "full bag" indicator for a compactor that uses a minimum number of additional parts and is easily installed during manufacture of the compactor.
Another object is to provide a "full bag" indicator for a compactor that uses existing electrical components for controlling the compactor to detect a full bag.
A further object of the invention is to provide a "full bag" indicator for a compactor that uses a mininum number of electrical components to maximize the reliability of the indicator.